The present invention relates to a method for molding a multilayer molded article. More particularly, the present invention relates to a method for producing a multilayer molded article, which method can produce a molded resin article having a skin material while preventing squeeze-out of a resin melt during molding and providing a molded article with no blanching, breakage of wrinkle of the skin material.
2. Description of the Related Art
Resin molded articles are widely used in many products including automobiles and household electric appliances, since such molded articles are economical and light and have good moldability.
Since resin molded articles have some draw-backs such that they have a poor appearance or a cool feeling and are easily flawed, it is desired to provide resin molded articles having good surface properties such as decorations and soft feeling.
Although many attempts have been made to provide desirable resin molded articles, it is impossible for a single resin to have satisfactory moldability and strength and also provide a molded article having good surface properties.
Presently, at least two materials having different functions are combined in a composite to produce a multilayer molded article comprising a resin body and a skin material.
As a method for producing the multilayer molded article, there is proposed a method comprising providing a resin melt and the skin material in a cavity formed in a mold which consists of male and female molds and closing the male and female molds whereby the molding of the resin and covering with the skin material are simultaneously done.
However, in this method, as shown in FIG. 1A, a part of a skin material 21 provided on a resin body 25 is strongly pulled during molding to cause blanching (22) or wrinkles (23) and in some case, said part is broken (24).
In addition, before the closing of the male and female is completed, a quantity of resin melt is squeezed out from an edge of the article to provide a molded article with a deformed shape as shown in FIG. 1B. Further, as shown in FIG. 1C, an edge part of the skin material 21 is broken and a part of the skin material 21 is peeled off to expose the resin body. Such articles have no commercial value.